/Engine/Source/Editor/AnimGraph/Public/AnimGraphNode_LayeredBoneBlend.h
Gives each visual node a chance to validate that they are still valid in the context of the compiled class, giving a last shot at error or warning generation after primary compilation is finished.
virtual void ValidateAnimNodeDuringCompilation ( class [USkeleton](API\Runtime\Engine\Animation\USkeleton) * ForSkeleton, class [FCompilerResultsLog](API\Editor\UnrealEd\Kismet2\FCompilerResultsLog) & MessageLog )